It is common practice to apply weight coat to a pipeline which is located in a water bottom area to protect the pipe from the elements and also to provide sufficient weight to maintain the pipeline submerged and in a non-buoyant condition. Weight coat is frequently made of a concrete material several inches thick which is applied around the circumference of the pipe and is usually applied to line pipe on each joint prior to adjacent joints of pipe being joined together by welding. The weight coat is applied to the full length of the pipe except for a short distance approximately one foot on each end. These exposed end portions are provided to facilitate welding adjacent exposed ends together to make up the pipeline. Various structures or devices have been employed from time to time to fill the space around the welded exposed pipe joint and between the adjacent sections of weight coat material. Examples of these prior art devices include devices such as are shown in U.S. Pat. Nos. 4,449,852; 4,103,505 and 4,102,137. Other weight coat prior art devices include patents such as U.S. Pat. Nos. 3,232,637 and 3,240,512 which are means for weighting underwater pipelines. None include structures such as the present invention which provides a relatively inexpensive and reliable protective sleeve that may be quickly and easily installed manually, i.e., with hand tools, as the pipe is being strung by the lay barge. The present invention does not require elaborate forming apparatus and is sufficiently strong to withstand impact by trawler boards and the concentrated stress imposed on the pipe by support rollers and particularly the end roller on the stringer attached to a lay barge.